The article revisits the work of Honório da Costa Monteiro Filho, highlighting his contribution to the study of economic botany and the taxonomy of Brazilian Malvaceae. Many of his seventy articles, are still cited. Yet little is known about his important role in educating agronomists involved with Brazilian flora and the creation of the Botanical Society of Brazil. These topics are discussed in the article, along with his work on a project to reform the teaching of agronomy in Brazil. The entire works of Monteiro Filho, archival documents, his correspondence with other scientists, and his observations on plant labels in herbaria were researched; interviews were also conducted with people with ties to him.